1. Field of the Invention
The present invention relates to a vehicle display device arranged in a vehicle having a function that automatically stops an engine when the vehicle temporarily stops.
2. Description of the Related Art
For example, Japanese Unexamined Patent Application Publication No. 2007-138926 discloses a technique of indicating that a driving state is in a fuel-efficient state.
Also, Japanese Unexamined Patent Application Publication Nos. 2007-297026, 2007-298022, 2007-298491, and 2007-298494 disclose a technique of providing an indication based on a deviation of a current instant fuel consumption with respect to an average fuel consumption in a past predetermined period of a vehicle, and indicating whether a current driving state decreases or increases the average fuel consumption of the vehicle by way of deflection of a needle of a meter.
The technique indicating whether the current driving state decreases the average fuel consumption of the vehicle is in effective because the technique allows an occupant to visually recognize that a change in fuel consumption of the vehicle depends on the driving state, and promotes the occupant to perform a driving operation with a decreased fuel consumption.
Further, an idling stop function is in practical use as a technique of decreasing a fuel consumption of a vehicle. The idling stop function automatically stops an engine when a vehicle temporarily stops and automatically restarts the engine by a predetermined driving operation.
When the technique disclosed in Japanese Unexamined Patent Application Publication Nos. 2007-297026, 2007-298022, 2007-298491, and 2007-298494 is applied to the vehicle having the idling stop function, if the vehicle is in an idling stop state, the speed and fuel consumption of the vehicle becomes 0. Thus, a fuel consumption is not calculated, and the position of a needle is not determined. Hence, during idling stop, the needle is moved to, for example, a position corresponding to a zero return position of a stepping motor which drives the needle.
The zero return position of the stepping motor which drives the needle is typically arranged outside the scale of the meter. Thus, the needle may be maximally deflected in a direction in the idling stop state with the technique disclosed in Japanese Unexamined Patent Application Publication Nos. 2007-297026, 2007-298022, 2007-298491, and 2007-298494.
Since the idling stop state with the speed and fuel consumption being 0 does not change the average fuel consumption of the vehicle, the maximum deflection of the needle in a direction in which the average fuel consumption is increased or a direction in which the average fuel consumption is decreased is an incorrect indication. This may provide the occupant uncomfortable feeling.